linux-ext4 - Re: 2nd Attempt

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 30 Apr 2013 10:14:41 -0600
From:	Andreas Dilger <adilger@...ger.ca>
To:	"<techweb@...world.com>" <techweb@...world.com>
Cc:	"<linux-ext4@...r.kernel.org>" <linux-ext4@...r.kernel.org>
Subject: Re: 2nd Attempt - FSCK Errors

On 2013-04-30, at 8:00, "Stephen Elliott" <techweb@...world.com> wrote:
> Just rebooted my box today after 200 days uptime and thought I'd request a volume scan and it found errors! I've never had a power outage etc so am keen to know what could have caused this file system corruption? Anyu ideas???
> 
> I'm running 4.2.21 on a ReadyNAS Pro6, but ultimately it is a Linux (Debian) 2.6.37.6. based system underneath. 
> 
> ***** File system check forced at Fri Apr 26 20:08:38 WEST 2013 ***** fsck 1.41.14 (22-Dec-2010) e2fsck 1.42.3 (14-May-2012) Pass 1: Checking inodes, blocks, and sizes Inode 4195619, i_blocks is 3135728, should be 3135904. Fix? yes

This is because the inode shows 176 sectors = 22 filesystem blocks
allocated than expected. Is this perhaps an extent format file? Try
"lsattr {filename}" and look for "e" in the file flags. 

> Running additional passes to resolve blocks claimed by more than one inode...
> Pass 1B: Rescanning for multiply-claimed blocks Multiply-claimed block(s) in inode 4195619: 167904376 167904377 167904378 167904379 167904380 167904381 167904382 167904383 167904384 167904385 167904386 167949296 167949297 167949298 167949299 167949300 167949301 167949302 167949303 167949304 167949305 167949306 Pass 1C: Scanning directories for inodes with multiply-claimed blocks Pass 1D: Reconciling multiply-claimed blocks (There are 1 inodes containing multiply-claimed blocks.

This is consistent with the one inode suddenly growing 22 blocks longer. 

> File /PREMIER/Premier Automation Purchase OrdersApp V18.5.mdb (inode #4195619, mod time Fri Apr 26 20:07:42 2013)
> has 22 multiply-claimed block(s), shared with 0 file(s):
> Multiply-claimed blocks already reassigned or cloned.

This could be failing if the duplicate blocks are inside the same file?
I don't know if that is something that e2fsck expects or not?  I wonder
if the extent tree is corrupted in some manner, but it isn't being detected
during the duplicate block scan.

This file looks big and important, so the first thing I would suggest is to
make a backup copy of it ASAP if you haven't already (having a
backup is always a good idea). Then, I'd suggest to update to
the latest e2fsprogs 1.42.7 and try again, since there was a
bug fixed in the e2fsck extent handling.

If that doesn't fix it, please dump the allocated file blocks with
"debugfs -c -R 'stat <4195619>' /dev/c/c" so we can see
what it looks like (probably gzipped
and as an attachment, since
it will be pretty large).

Cheers, Andreas--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html